The present invention relates generally to electronic musical instruments and particularly concerns improved automatic accompaniment systems for electronic musical instruments.
Electronic musical instruments, most notably of the keyboard variety, which are capable of automatically playing a musical pattern or rhythm to accompany a melody played by a performer are well known in the art. The automatic accompaniment can be created in a variety of different styles and the instrumentation, rhythm and chord patterns can be changed by the performer to add variety to the accompaniment. U.S. Pat. No. 4,433,601 to Hall et al. is exemplary of an electronic keyboard musical instrument having such an automatic accompaniment capability.
The automatic accompaniment generated by prior art instruments is often multitimbral and may include for instance, a drum section, a bass line and a string section. During the performance of the musical piece, a preset balance is typically maintained between the various sections and can only be changed by altering the level setting established for the different sections by the use of sliders or other similar controllers. Manipulation of these controllers by the performer is cumbersome and detracts from the performance of the musical piece. In addition, subtle real time nuances in the orchestral balance are extremely difficult if not impossible to achieve.
Prior art automatic accompaniment generators also do not allow for real time variation of the relative balance between plural instruments contained in the same single section of the accompaniment. For example, it may be desirable to accent the sustained string sounds with occasional trumpet "stabs", or a countermelody played on a trombone, scored in the same accompaniment section and recalled at the discretion of the performer.
It is known in the art to effect level control in a keyboard electronic musical instrument in response to key velocity or key aftertouch force. However, the entire performance is equally effected by the level change introduced by this approach thereby leaving the original balance between the different instrument sections, or the relative balance between the instruments of a given single section, unaltered.
The foregoing limitations of prior art automatic accompaniment generators, and particularly performance level controllers used in association therewith, do not allow for a true representation of the playing of a real live orchestra, where the balance constantly changes, and the instrumental sections are faded in and out, following the demands of the musical score.
It is therefore a basic object of the present invention to provide an improved automatic accompaniment system for an electronic musical instrument.
It is a further object of the invention to provide an improved system for controlling the level balance during the playback of an automatic accompaniment in an electronic musical instrument.
It is yet another object of the invention to provide a system which affords real time control by the performer of the level balance between the different instrumental sections, or the relative balance between the instruments of a given single section, of an automatic accompaniment.
It is still a further object of the invention to provide a level balance control system for an electronic musical instrument which may be conveniently operated by the performer with a minimum of effort and whose operation results in a more natural and less mechanical performance of automatic accompaniment patterns.